. >> billionaire warren buffett, an obama ally today wrote an editorial in "the new york times," calling for a higher minimum tax for the wealthy. >>> a shake-up in the middle east in politics today as an israeli moderate resigns. israeli defense minister ehud barack abruptly quit politics today, saying he'll only finish out his term. the obama administration had embraced him as a moderate influence on benjamin netanyahu's hard-line policies. meanwhile, a leader of hamas is warning that a fragile ceasefire in gaza could flare back into violence if negotiators don't come to agreement quickly. negotiations have to proceed through egyptian messagers because israel and the united states consider hamas a terrorist organization. >>> still ahead here at 5:00, it's a distinction that universities don't want. the bay area school, though, near the top of this dubious list. >>> and a blockbuster acquisition that never was. google tied to a takeover deal the company is now calling a hoax. >>> and a celebration filled with secret information. how sensitive information might have been leaked in the ma